That is probably because RWPaint does not work in indexed mode and rather converts the image to full 32bit RGBA when loaded. This allows you to use any colors and drawing tools without explicitly setting image mode like in some other editors. The palette is then generated again (or not) when the file is being saved - depending on the file format and the image. As long as the resulting image looks exactly the same, the indices are technical detail, right? If you need to preserve them, you should use an editor that works in indexed mode internally.

c-sanchezon October 3rd 2017

I see.But please, can you add at least an option to save and load palette?so, we can save original palette, and use that palette when saving to 256 colors?